ABSTRACT

The logician Eubulides of Miletus, a contemporary of Aristotle, was famous for seven puzzles. One was the Liar: if a man says that he is lying, is he telling the truth? Another was the Hooded Man: how can you know your brother when you do not know that hooded man, who is in fact your brother? The Electra turned on the delusion of Orestes in his madness, who took his sister Electra for a Fury. The Elusive Man will appear later. There was also the Horned Man: since you still have what you have not lost, and you have not lost horns, you still have them (hence the horns of a dilemma). The remaining puzzles were the Bald Man and (accompanying five men and one woman) the Heap. In antiquity they were usually formulated as series of questions.2